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Badges: 12
Report Thread starter 14 years ago
I have a question that I can't solve. Could someone tell me the right answer along with how they obtained it?

Q - The densities of water and steam are 1.0 X 10^3 kg/m3 and 6.1 X 10^-1 kg/m3 respectively.

What is the ratio: (Average seperation of steam molecules)/(Average seperation of water molecules) ?

A- 12 B- 40 C- 250 D- 1000
john !!
Badges: 14
Report 14 years ago
as a water molecule has the same mass as a steam molecule, you can say the mole density (molecules per volume) is the same.

so in one metre cubed there are x molecules of water and y molecules of steam, where
y/x = 6.1*10^-1 / 1*10^3 = 6.1*10^-4

however we want to convert to a length from a volume, so we find the cube root:
cube root = 0.08480
the inverse of this is 11.7 or something, close enough for my liking to 12.
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